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United States Patent | 5,202,631 |
Harms ,   et al. | April 13, 1993 |
Method for producing an image of an object, for example, tissue having fat and water components. A uniform magnetic field is generated to magnetize the object. A shaped pulse sequence is selected for each of waveform, phase and frequency components of an RF signal. An RF signal which includes the selected waveform, amplitude and frequency pulse sequences is generated to produce transverse magnetization in the object. First, second, and third changing magnetic fields are then generated in the object and a series of gradient echoes are produced in response thereto. From the gradient echoes, an image of the object may be produced.
Inventors: | Harms; Steven E. (3100 Beverly Dr., Dallas, TX 75205); Flamig; Duane P. (1411 Scottsboro La., Richardson, TX 75082); Griffey; Richard H. (San Marcos, CA) |
Assignee: | Harms; Steven E. (Dallas, TX); Flamig; Duane P. (Dallas, TX) |
Appl. No.: | 743523 |
Filed: | August 9, 1991 |
Current U.S. Class: | 324/309; 324/307 |
Intern'l Class: | G01R 033/20 |
Field of Search: | 324/300,307,309,310,311,312,313,314,318,322 128/653.2,653.5 |
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4734647 | Mar., 1988 | Yoshimura | 324/318. |
4746864 | May., 1988 | Satoh | 324/309. |
4799016 | Jan., 1989 | Rezvani | 324/318. |
4833409 | May., 1989 | Eash | 324/318. |
4843322 | Jun., 1989 | Glover | 324/309. |
4857843 | Aug., 1989 | Macovski | 324/307. |
4987371 | Jan., 1991 | Glover et al. | 324/320. |
5079505 | Jan., 1992 | Deimling et al. | 324/311. |
Steven E. Harms "Three-Dimensional and Dynamic MR Imaging of the Musculoskeletal System", (Nov. 1990). Harms and Muschler, "Three Dimensional MR Imaging of the Knee Using Surface Coils," Journal of Computer Assisted Tomography; 10(5):773-777 (1986). Sherry et al., "Spinal MR Imaging: Multiplanar Representation from a Single High Resolution 3 D Acquistion," Journal of Computer Assisted Tomography; 11(5):859-862 (1987). Robert L. Tyrrell, "Fast Three-Dimensional MR Imaging of the Knee: Comparison with Arthroscopy", Radiology; 166:865-872. Charles E. Spritzer, et al., "MR Imaging of the Knee: Preliminary Results with a 3DFT GRASS Pulse Sequence", American Journal of Roentology; 150: 597-603 (1988). Alan M. Haggar et al.,"Meniscal Abnormalities of the Knee: 3DFT Fast Scan GRASS MR Imaging", American Journal of Roentology; 150: 1341-1344 (1988). "Method Combines Vascular, Anatomic Data", Diagnostic Imaging: 140-141 (Feb. 1991). Harms et al.; "Clinical Application of a New Fat Suppressed, Steady State Pulse Sequence for High Resolution Acquisitions" Book of Abstracts; vol. 1, Society of Magnetic Resonance in Media; 187; Aug. 18, 1990. Herbert Y. Kressel, et al., ed., "New MR Pulse Sequence: Fat-Suppressed Steady State", Syllabus: Special Course, MR 1990, Radiological Society of North America (Nov. 1990). "RSNA '90 Meeting Notes," Radiology 1991; 178:559 (1991). Yaguinto et al., "Arterial Injury from Penetrating Trauma: Evaluation with Single Acquisition Fat Suppressed MR Imaging; American Journal of Roentology"; 158:631-633 (Mar. 1992). Pierce et al., "Three Dimensional Gadolinium-Enhanced MR Imaging of the Breast: Pulse Sequence with Fat Supression and Magnetization Transfer Constrast"; Radiology 181: 757-763 (1991). Harms et al., "Three-Dimensional Imaging", Magnetic Resonance Imaging of the Body, Second Edition Raven Press Ltd.; 199-215 (1992). |